The present invention relates to a semiconductor device having a semiconductor element equipped with an electrode on an electrode patterned surface for external connection, and to a semiconductor assembly including a work piece having the semiconductor device mounted thereon.
As a semiconductor device assembly including a semiconductor device having a semiconductor element package, an assembly is known in which an electrode projection, e.g. a solder bump, provided on the semiconductor device are joined to a corresponding circuitry electrode of a work piece. In order to ensure reliability in the assembly after the mounting, it is necessary to reduce stress exerted on a joint at the electrode projection such as the solder bump.
In a conventional semiconductor assembly, stress is derived from a difference of respective thermal expansions between the semiconductor element and the work piece due to a change in an ambient temperature after the mounting, and the stress concentrates particularly on the joint. The thermal stress, which is repeatedly exerted at upon heat cycling, may injure the joint and thus impair the reliability after the mounting.
A semiconductor device and a semiconductor device assembly are provided and both ensure reliability after mounting.
The semiconductor device includes a semiconductor element having an electrode patterned surface and an external connection electrode provided on the electrode patterned surface. Under the situation where the external connection electrode is joined to a corresponding circuitry electrode on a work piece, the semiconductor element can deflect between two adjacent external connection electrodes according to a contraction displacement of the work piece.